Institute of Biotechnology and Biomedicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain; Department of Cell Biology, Physiology and Immunology, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
Institute of Biotechnology and Biomedicine, Universitat Autònoma de Barcelona, 08193, Bellaterra, Spain.
Environ Res. 2022 Sep;212(Pt A):113433. doi: 10.1016/j.envres.2022.113433. Epub 2022 May 14.
The extent of the widespread, planetary contamination by plastic waste is difficult to fully capture. Nanoplastics (NPs) are currently in the center of research concerning plastic litter, both for the analytical challenges they pose and for their potential to provoke hazardous effects in organisms. However, there are still many unanswered questions in this multidisciplinary field, with a crucial missing piece being the quantification of NPs in fish tissues after in vivo exposures. Another relevant question that is still greatly unexplored is how a chronic exposure to NPs will affect fish health. This study aims to provide answers to both of these relevant knowledge gaps. To this end, goldfish (Carassius auratus) were exposed to 44 nm polystyrene (PS)-NPs via water for 30 days. Following the exposure, gastrointestinal tract, liver and muscle were sampled for PS-NPs analysis by means of size exclusion chromatography coupled to high resolution mass spectrometry. PS-NPs were detected in all liver and muscle samples of exposed fish, with higher concentrations in liver than in muscle, whereas no PS-NPs were detected in the gastrointestinal tract. Nevertheless, exposure to PS-NPs did not induce changes in hematology parameters nor in cortisol and glucose levels in plasma. On the other hand, even a relatively low concentration of PS-NPs was able to cause DNA damage, measured by an increase in erythrocyte nuclear abnormalities, suggesting that PS-NPs can reach the cell nucleus and cause genotoxicity. These results show for the first time that PS-NPs find their way to fish muscle after chronic exposure, where they bioaccumulate, but do not alter fish survival nor hematological or physiological stress indicators. The accumulation of PS-NPs in fish muscle can represent a threat to human health as a possible route of exposure to small-sized plastics. The present results in a model fish species open windows for future studies in edible fish species.
塑料废弃物的广泛、全球性污染程度难以全面捕捉。纳米塑料（NPs）目前是塑料垃圾研究的中心，既因为它们带来的分析挑战，也因为它们有可能对生物体产生有害影响。然而，在这个多学科领域仍有许多悬而未决的问题，其中一个关键的缺失环节是在体内暴露后量化鱼类组织中的 NPs。另一个仍未得到充分探索的相关问题是，NPs 的慢性暴露将如何影响鱼类健康。本研究旨在回答这两个相关的知识空白。为此，金鱼（Carassius auratus）通过水暴露于 44nm 聚苯乙烯（PS）-NPs 30 天。暴露后，通过尺寸排阻色谱法与高分辨率质谱法联用，对胃肠道、肝脏和肌肉进行 PS-NPs 分析。暴露鱼的所有肝脏和肌肉样本中均检测到 PS-NPs，肝脏中的浓度高于肌肉，而胃肠道中未检测到 PS-NPs。然而，暴露于 PS-NPs 并未导致血液学参数、血浆皮质醇和葡萄糖水平发生变化。另一方面，即使 PS-NPs 的浓度相对较低，也能引起红细胞核异常增加导致的 DNA 损伤，表明 PS-NPs 能够到达细胞核并引起遗传毒性。这些结果首次表明，PS-NPs 在慢性暴露后会进入鱼类肌肉并在其中生物累积，但不会改变鱼类的生存能力或血液学或生理应激指标。PS-NPs 在鱼类肌肉中的积累可能对人类健康构成威胁，因为这是接触小尺寸塑料的一种可能途径。本研究结果为食用鱼类物种的未来研究开辟了新的窗口。
